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Graphical abstract Highlights • Dencichine is significantly correlated with the selenium content in P. notoginseng. • There is a significant correlation between dencichine and selenium content in soil. • Selenium promotes the accumulation of dencichine in P. notoginseng. • Dencichine increases the antioxidant capacity of P. notoginseng. • Dencichine improves the stress resistance of P. notoginseng. Abstract Dencichine is the main ingredient in Panax notoginseng, which is an herb that plays a key role in hemostasis. The biosynthesis of dencichine requires the participation of sulfur. Selenium and sulfur are congeners. The purpose of this study was to reveal if selenium participates in the synthesis of dencichine, and to determine whether dencichine plays a role in anti-stress effects. P. notoginseng and planting soil were sampled from different sites and subjected to selenium and dencichine determinations. Biosynthesis of dencichine was investigated by exposing the seedlings to different selenium concentrations in pot and hydroponic experiments. The effects of dencichine on the regulation of the antioxidant enzyme system and reactive oxygen species (ROS) were also tested in hydroponic experiments. The results indicated that the selenium and dencichine contents of roots were 0.69-0.98% and 0.21–1.18 mg kg−1, respectively, and the soil selenium content in 18 planting areas in Yunnan Province was 0.16-0.32 mg kg−1. Dencichine and selenium contents in soil or plants were positively correlated (R2 = 0.1643***, R2 = 0.3084***, respectively). Selenium treatment increased the dencichine content by 69–111% in pot experiments using 5 mg kg−1 and by 23–33% in hydroponic experiments using 2 μM. The key genes in the dencichine biosynthetic pathway, such as β-cyanoalanine synthase and serine acetyltransferase , were significantly upregulated by the 2 μM selenium treatment. Dencichine treatment (30 μM) significantly enhanced root activity, increased antioxidant capacity, decreased ROS content, and reduced lipid peroxidation of the cell membranes. Therefore, selenium promoted the synthesis of dencichine, which acted as an anti-stress agent in P. notoginseng. However, the selenium content was deficient in the P. notoginseng planting soil from Yunnan Province. These results suggest that appropriate selenium supplementation is beneficial for the growth and development of P. notoginseng and the accumulation of dencichine. [ABSTRACT FROM AUTHOR]

• The 45S and 5S linked-type rDNA was first identified in Artemisia annua. • Rich polymorphisms of copy number and sequence of rDNA were identified in Artemisia annua. • Hot spots of polymorphic sites concentrated in non-coding regions of rDNA. • ITS2 haplotype analysis is ideal tool for Artemisia. annua strain identification and population genetic homogeneity assessment. Artemisia annua , a well-known traditional Chinese medicine, is the main source for production of artemisinin, an anti-malaria drug. A. annua is distributed globally, with great diversity of morphological characteristics and artemisinin contents. Diverse traits among A. annua populations impeded the stable production of artemisinin, which needs an efficient tool to identify strains and assess population genetic homogeneity. In this study, ribosomal DNA (rDNA), were characterized for A. annua for strains identification and population genetic homogeneity assessment. The ribosomal RNA (rRNA) genes were identified using cmscan and assembled using rDNA unit of LQ-9 as a reference. rDNA among Asteraceae species were compared performing with 45S rDNA. The rDNA copy number was calculated based on sequencing depth. The polymorphisms of rDNA sequences were identified with bam-readcount, and confirmed by Sanger sequencing and restriction enzyme experiment. The ITS2 amplicon sequencing was used to verify the stability of ITS2 haplotype analysis. Different from other Asteraceae species, 45S and 5S linked-type rDNA was only found in Artemisia genus. Rich polymorphisms of copy number and sequence of rDNA were identified in A. annua population. The haplotype composition of internal transcribed spacer 2 (ITS2) region which had moderate sequence polymorphism and relative short size was significantly different among A. annua strains. A population discrimination method was developed based on ITS2 haplotype analysis with high-throughput sequencing. This study provides comprehensive characteristics of rDNA and suggests that ITS2 haplotype analysis is ideal tool for A. annua strain identification and population genetic homogeneity assessment. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: We deploy a time-dependent Born–Oppenheimer approximation approach for numerically solving the time-dependent Schrödinger equation (TDSE) by reducing the wavefunction dimensionality to nuclear and electronic degrees of freedom, and apply it to a one-dimensional model of H2 +. Based upon our three distinct error evaluation schemes, we quantitatively compare the wavefunctions and HHG spectra which are computed by the present approximation method, with those obtained by fully solving the TDSE. The similarities of both the wavefunctions and the HHG spectra justify that our approach is feasibly precise for medium laser intensity. It is also anticipated that this approximation can be adopted for other polyatomic molecules with a dimensionality reduction and computational simplification in calculating the time-dependent wavefunctions. [Copyright &y& Elsevier]

Highlights • Robust city-level CO 2 emission inventory for China was benchmarked for 2005. • A combination of CHRED database, statistical data and survey data was considered. • Megacities or dominant coal/iron/steel-producing cities had high CO 2 emissions. • Industrial structure, city scale and climate greatly affected per capita CO 2 emissions. Abstract Year 2005 is important because it is the base year for the international carbon reduction commitment and national development plans for China. However, accurate and robust CO 2 emission data for 2005 remain limited, particularly for city-level emissions. To address these gaps, we established a uniform city-level CO 2 emission inventory for all the 287 prefecture-level cities in China for 2005, combining the High-Resolution Emission Gridded Database (CHRED) 2.0, statistical data and onsite survey. The results showed that Shanghai, Tangshan, Beijing, Tianjin, Jining, Handan, Chongqing, Suzhou, Shijiazhuang and Wuhan were the ten cities with greatest CO 2 emissions in 2005, with total CO 2 emissions of 205, 184, 145, 126, 116, 103, 96, 93, 90 and 81 Mt, respectively. These cities were either megacities or those dominated by coal, iron or steel production. However, the three cities with the highest CO 2 emissions per GDP and CO 2 emissions per capita were Jiayuguan, Wuhai and Shizuishan, which were dominated by industry, small- or medium-sized, and exhibited a high demand for heat and cooling. Cluster analysis revealed that industrial energy consumption was the dominant emission source for most cities, except Haikou and Lhasa, for which indirect CO 2 emissions were dominant. This study will greatly contribute to the city level CO 2 emission inventory and research on China. [ABSTRACT FROM AUTHOR]

Scuteformoids A-J, ten previously undescribed neo- clerodane diterpenoids along with one known analogue, were isolated from petroleum ether soluable fraction of the whole plants of Scutellaria formosana . The differences among these compounds are the substituents and stereochemistry at C-13. Their structures were elucidated by 1D and 2D NMR experiments, and the absolute configurations of Scuteformoids A, C, E, F, and I were further confirmed by single-crystal X-ray diffraction. Scuteformoids A, C, D, F, H, and I were evaluated for their inhibitory effects against HIV lytic replication and cytotoxic activities. All of them showed weak anti-HIV activities, with EC 50 values ranging from 48.24 to 79.17 μg/mL. [ABSTRACT FROM AUTHOR]

• A GHG emissions inventory for 305 Chinese cities is compiled for 2015. • Emissions of CO2, CH4, N2O, and fluorinated GHGs are separately accounted. • The uncertainty of city-level GHG emissions is analyzed. Accounting and understanding greenhouse gas (GHG) emissions at the city level are of great importance because cities are the focus of future mitigation and adaption activities to address climate change, especially in developing nations like China. However, existing studies have not yet provided a complete and updated emissions inventory of city-level GHGs for China in terms of city and GHG-type coverage. In this paper, we rigorously assemble a dataset that contains GHG emissions including carbon dioxide, methane, nitrous oxide, and fluorinated GHGs for 305 Chinese cities, based on a high-resolution emissions database (China High-Resolution Emission Database, CHRED 3.0) and first-hand on-site data collection and verification by 19 groups of 137 researchers using a bottom-up method, and analyze the uncertainty of the emissions. Results show that total GHG emissions are high in cities in eastern China and low in cities in west, while per capita GHG emissions are high in northern cities and low in southern cities. The emissions of four types of GHGs (CO 2 , CH 4 , N 2 O and fluoridated GHGs) share different spatial distributions, due to variant industrial structure, energy structure, industry point sources and agricultural surface sources, etc. The uncertainty of GHG emissions is highly related to the source data of cities. Finally, we propose policy recommendations, including improving data quality and strengthening competitions of city-level emission reduction, to improve city-level emissions data integrity and low-carbon development strategies. [ABSTRACT FROM AUTHOR]